Incinerator



July 3, 1956 T. J. KEENAN, JR

INCINERATOR 5 Sheets-Sheet 2 Filed Jan. 21, 1952 IN VEN TOR.

THOMAS J. KEE/VA/V JR.

A T TORNE Y5 y 3, W56 T. J. KEENAN, JR 2,752,869

INCINERATOR Filed Jan. 21, 1952 5 Sheets-Sheet 3 INVENTOR. T'NOfl MS J-NEE/VA/VMW.

Jufly 3, 19% "r. J. KEENAN, JR

INCINERATOR 5 Sheets-Sheet 4 Filed Jan. 21, 1952 July 3, 1956 T. J.KEENAN, JR"

INCINERATOR Filed Jan. 21, 1952 5 Sheets-Sheet. 5

INVENTOR. THOMAS J. NEE/VAN JR humaami /MMM ATTORNEYS llNClNERATORThomas J. Keenan, Jr., Oakland, Calif., assignor to Oakland ScavengerCompany, Oakland, Calif., a corporation of California ApplicationJanuary 21, 1952, Serial N0. 267,430

7 Claims. (Cl. 110-7) This invention relates to new and usefulimprovements in refuse incinerator and constitutes an improvement overPatent No. 2,481,504, issued September 13, 1949, to Ferro et al.

The instant invention employs a plurality of traveling grates arrangedso that refuse is dumped onto the uppermost grate at the rear of thecombustion chamber, is moved forwardly on said grate and is dischargedtherefrom onto the next grate in order, each succeeding grate being at alower elevation than the preceding one. A fuel such as gas or oil isinjected adjacent the lowermost grate, and the heat of the burningrefuse, together with the heat of the fuel injected is used to evaporatemoisture and burn the refuse on the grates at higher elevations.

One feature of this invention is the fact that the roof of the chamberin which the grates are installed is stepped, and at the rearward end ofeach step a drop wall is provided downwardly disposed at an angle ofapproximately 45 to the juncture of the riser of the next step in order.This construction hereinafter described in detail, promotes turbulenceof the gases within the incinerator and thereby avoids stratification ofthe air and gases within the chamber and improves combustion by insuringthorough exposure of the refuse to oxygen.

Turbulence is also increased by the provision of hot air inlet nozzlesin the side walls of the chamber adjacent the grate surfaces, saidnozzles being staggered in angu lar relation so that all areas of thegrate surface are subjected to blasts of air, and the zones of thegrates intermediate the side walls are subjected to an equal amount ofair with the zones adjacent the side walls. The combination of dropwalls and air nozzles which has been described insures better combustionthan is present in incinerators of the general type of the present invention which have heretofore been employed.

Another feature of the present invention is the employment of louversforming the floor of the combustion chamber immediately beneath thegrates. Said louvers are arranged to be tilted periodically, so that thefines and non-combustible material may be discharged from the floorbeneath the grates.

Beneath the louvers and extending below the combustion chamber forapproximately the full length thereof is a continuous conveyor whichreceives the sinter discharged from the lowermost grate and alsoreceives the fines which drop when the louvers are opened. A water spraysystem is provided to quench the hot material on said conveyor so thaton the discharge of the said conveyor said material may be safelyhandled. Said conveyor is preferably made of sectional steel pans soconstructed that intermediate the ends of said conveyor a substantiallyuninterrupted imperforate surface is provided.

Another feature of the instant invention is the fact that each grate ofthe series of grates is individually t driven, with adjustable speed.This feature is of im- 2,7523% Patented .lluly 3, 1956 portance in thatit has been found that various types of refuse vary in consistency fromday to day and hence it is important that the grates be adjustable sothat their velocity may be suited to the condition of the refuse beinghandled at any particular time.

Other objects of the present invention will become apparent upon readingthe following specification and referring to the accompanying drawingsin which similar characters of reference represent corresponding partsin each of the several views.

In the drawings:

Fig. l is vertical longitudinal midsection through the interior of thecombustion chamber.

Fig. 2 is a transverse vertical section taken substantially along theline 2-2 of Fig. 1.

Fig. 3 is a side elevation of the exterior of the combustion chamber.

Fig. 4 is a fragmentary vertical section of the side wall of thecombustion chamber showing an enlarged detail of one of the over fireair ports, taken substantially along the line 44 of Fig. 1.

Fig. 5 is a section similar to Fig. 4 showing another of such over fireports, taken substantially along the line 5-5 of Fig. 1.

Fig. 6 is similar to Fig. 4 showing another such over fire air port,taken substantially along the line 6-6 of Fig. 1.

Fig. 7 is a fragmentary sectional view of a portion of the drop wall ofthe roof construction showing a drop wall nozzle detail.

Fig. 8 is an enlarged side elevation of the linkage system for tiltingthe louvers.

Fig. 9 is a fragmentary vertical longitudinal mid-section through theinterior of a modified combustion chamber.

Fig. 10 is a side elevation of a portion of a conveyor employed inconnection with this invention.

Fig. 11 is a transverse vertical section taken substantially along theline 11-11 of Fig. 10.

The instant incinerator is designed primarily for a relatively largescale operation wherein garbage, trash, and other industrial andhousehold refuse is collected by scavengers in trucks; useful materialsare salvaged; and the remainder is incinerated. Complete combustion ofthe refuse is essential for the avoidance of objectionable odors andsmoke and further to eliminate the problem of disposal of matter whichis not completely burned. Accordingly, there is provided a long narrowcombustion chamber 2% having exterior side walls 21, a front wall 22,and a rear wall 23, and a roof 24 of novel construction. In the regionof the combustion chamber all said walls are formed of refractorymaterial. Said roof 24 is stepped upwardly from front to rear atdifferent elevations which are hereinafter disclosed. A riser 27 isprovided at the front of each step 28, said riser extending downsubstantially below the level of the horizontal portion of the roof stepin front of said riser. An angularly disposed drop wall 29 joins thebottom of said riser with the horizontal stretch of the stepped roofportion in front of said riser, said walls 29 making about a 45 anglewith the horizontal. The roof configuration is best shown in Fig. 1, itbeing apparent that the top of combustion chamber 20 is broken up by thesteps 28 and angularly disposed drop walls 29. The function of thisarrangement of the roof of the combustion chamber is to break up thepath of the hot gases passing from the front of the chamber to the rearand promote turbulence, thereby preventing stratification of the gaseswithin the combustion chamber and to effect the impingement of the hotgases upon the material on the grates. The roof and sides of thecombustion chamber may be supported from external vertical andhorizontal beams 31 and 32, respectively.

Refuse is deposited in hopper 33 at the rear of the combustion chamberabove the roof thereof and is carried by a horizontal movable belt 3 tochute 36 which extends downwardly at the rear of the uppermost grate 37of the series of grates 2d. A wall is provided to impede gases tendingto discharge upwardly through chute 36.

Each traveling grate 2'6 is supported horizontal at its upper and lowerstretches by a plurality of transverse, horizontal, idler rollers whichrollers prevent sag of the grates. Rollers 4!. pass through side walls21 and are journalled on the exterior by pillow blocks 42. Sprocket 43at the forward end of grate 2-6 is driven by shaft 44 which extends outthrough side wall 21 and is driven by motor as. Said motor is adjustablein speed so that the rate of travel on the grate 26 may be controlied.Each grate 2s proceeding from rear to front of the incinerator chambers28 is stepped downwardly at a lower elevation, its rearward endextending under the forward end of the preceding grate to receive allthe material discharged therefrom. It may be understood, as hasheretofore been stated, each grate of the series of grates isindividually driven and controlled.

interior side walls 21 and walls 47 close olf on an air duct 28 whichextends longitudinally along each side of the exterior of combustionchamber 2'9, the air in said duets being preheated by means ofconventional heat exchanger or pre-heater (not shown). A plurality ofports 51 is formed in interior side wall 21 communicating from said duct48 to combustion chamber 25) as shown particularly in Figs. 2, 4, and 6,there being a set of nozzles 52 for each grate disposed in each sidewall 21 opposite each grate 26 and above the level of the upper stretch.The angle which respect to the vertical of each nozzle 52; of each setof nozzles, as shown particularly in Figs. 4-6 varies. Therefore, thedistance out from the side wall and toward the center of the grate atwhich air is directed varies for each nozzle and the resultant of theplurality of nozzles 52, 52a, 52b, and 52c, is to subject the entireupper stretch surface of grate 26 to air blast. Combustion is thusuniform throughout grate Z5 regardless of the distance from the sidewalls. It will be understood that air is supplied through ports 51 underdraft from blower not shown) and controlled by suitable valves (notshown).

As has been stated, grates 26 are staggered in elevation, the highestgrate 37 being at the back and the lowermost 53 being at the front ofthe combustion chamber 20. Vertical bulkheads 54 are disposed at therear end of each grate 26, said bulkheads and normally closed louvers 56forming a stepped floor d7 beneath grates 26.

Over fire nozzles 61 are disposed in front wall 22, and directed towardlower most grate 53, said nozzles being oil or gas fired as desired. Theflame of said nozzles 61 ignites the refuse on said lowermost grate 53and the heat of the burning refuse evaporates the moisture in the refuseand initiates combustion. The heat rising from lowermost grate 53 iscarried upwardly to the grates 26 disposed rearwardly and evaporates themoisture of as well as burning the refuse thereupon. The spent hot gasesmay be discharged from the combustion chamber through opening 62 in sidewall 21 over uppermost grate 37, and after subsequent treatments whichare optional and form no part of this invention escape up the stack (notshown) to atmosphere. It will be understood that the heat of combustionwithin combustion chamber is such that the stack gases are free of odorand smoke, and hence, do not constitute a nuisance to the neighboringcommunity. To insure against the escape of objectionable odors andsmoke, standard precipitators and scrubbers and the like may be employedas required.

Lowermost grate 53 discharges through opening 63 .4 adjacent the frontof combustion chamber 20 and the spent refuse drops upon the top stretchof upwardly and rearwardly moving conveyor 66, which preferably extendsbelow combustion chamber 29 for the full length thereof. Said conveyor66, which may be of the type known as the No Leak apron conveyormanufactured by Link-Belt Company, is made up of a plurality ofconnected steel pans 67 linked together and passing over sheaves 63 ateach end through which the conveyor is driven. Said conveyor on is soconstructed that the refuse and moisture deposited thereon does not passthrough, but is held in the individual pans 67 which make up theconveyor. Each said pan 67 comprises a substantially rectangular bottom82 and upwardly, outwardly diverging sides 83. The sides 33, as bestshown in Fig. 30, have their front and rear edges 84 upwardly diverging.The adjacent pans 67 are interleaved, as best shown in Fig. 11, so thata tight joint is obtained. The forward and rearward edges of the bottom32 are formed with a roll $6 which likewise facilitates forming of atight joint and also facilitates locking and unlocking of the pans 67 asthe conveyor passes around the end sprockets 68. Each of the pans 67 ismounted on a continuous conveyor chain of the link type 87 which has anadapter link 88 connected thereto. The chains 37 are connected atalternate links to wheels 89 supported by tracks 91. Accordingly, thechain 87 is advanced by its driving sprocket and supported by wheels 89running on tracks $31. In its straight stretches, the rolled edges 36 ofthe adjacent pans are in tight contact, which prevents air or waterpassing through the conveyor, and the side edges 33 are likewiseinterlocked. However, at the turns around the sprockets, the pans arecapable of unfolding to permit the turning movement. Disposed above theconveyor 66 are water pipes as provided with spray heads 71 arranged tospray water upon the pans e"; and thus quench the hot spent materialthereon so that w ten the material is discharged at the end of theconveyor 66 into discharge hopper 72 it is relativ-my cool and may beconveyed away without fire hazard.

Below grates 2.6 and closing off said grates from conveyor 66 ishorizontal stepped flooring 57 made up of vertical bulkheads 54 and aplurality of normally approximately horizontal disposed, transverselouvers 56. When in closed position said louvers overlap and provide acontinuous flooring beneath grates 26 upon which fines dropping fromgrates 26 are collected. Said louvers are supported by tiltabletransverse, horizontally disposed square shafts 76 extending out throughside walls 21, each said shaft 76 being attached to round shaft 77 theouter end of which bears crank '73 which is in turn fastened tohorizontally slidable link 79. It will be seen particularly withreference to Fig. 1 that louvers 56 are arranged in horizontal stretchescorresponding to the horizontal grates 26. All of the louvers 56 in agiven stretch are connected to a single link '79. Thus, by sliding link79 all of the louvers of a stretch are tilted simultaneously andaccordingly the fines drop onto pan conveyor 66, and are ultimatelycarried out to discharge hopper 72. The tilting of the louvers 56 thusenables cleaning of the floor 57 of combustion chamber 20 when requiredwithout interference with operation of the incinerator. In closedposition said louvers 56 overlap slightly and are approximatelyhorizontal and prevent air or gases within the incinerator chamber 20from escaping. It will be noted particularly with reference to Fig. 2that beneath louvers 56 slanting side skirts 81- direct the finesdropping through louvers 56 toward the center of the structure and ontopan conveyor 66.

Operation Refuse is deposited in hopper 33 and continuously carried byconveyor 34 to chute 36 Where it drops down to the rear of the uppermostmoving grate 37. The refuse subjected to hot gases liberated in lowersteps of incinerating chamber 2! which vaporize moisture and initiatecombustion of the combustible material in the refuse. The speed of thegrate 37, as well as the subsequent grates upon which refuse isdisposed, is regulated so as to accomplish most complete combustionbeing regulated to suit and accommodate the type and composition ofrefuse handled at any particular time. As required, external heat may beapplied in the form of gas or oil fuel through nozzles 61. Heated air isforced across the upper stretch of the grate 26 to support combustion ofthe combustible material through ports 51, nozzles 52 thereof disposedin such fashion as to subject the entire surface of grate 26 to air. Airto support combustion and promote turbulence is also forced through roofnozzles 61. Refuse is discharged from the forwardrnost end of each grateonto the rearmost end of the next lower grate in order, and thence fromstep to step to lowermost grate 53 which in turn discharges throughopening 63 onto rearwardly moving pan conveyor 66 which moves the sinterup to discharge hopper 72, the sinter meanwhile being subjected toquenching action of water spray 71. As fines collect on top of louvers56 from time to time the attendant tilts louvers 56 by longitudinalmovement of links '79 whereupon the fines drop onto conveyor 66.

A modified form of incinerator chamber is shown in Fig. 9. it will beobserved that instead of the grates 26 being disposed horizontally, saidgrates are inclined at an angle of approximately with respect to thehorizontal. It will be understood that the angle selected may varydepending upon the class of material being handled. Refuse travels downthe sloping grates and is subjected to a more complete combustion byreason of the greater area of burning surface and the angle with respectthereto at which the gases impinge upon the grate surface.

I claim:

1. An incinerator for refuse comprising means forming an elongatedincinerator chamber, a roof for said chamber having a series of stepsstepping downwardly from rear to front, formed by substantiallyhorizontal portions, substantially vertical riser portions, andangularly disposed connecting portions downwardly inclined from therearward end of each horizontal portion to the bottom of the adjacentriser, a series of stepped traveling grates within said chambercorresponding to said steps of said roof, the forward end of one gratebeing arranged to discharge upon the rearward end of the next lowermostgrate, said vertical risers terminating a substantial distance above thegrate underlying said risers to permit flow of combustion gases from thelower to the upper grates, means for supplying air to support combustionto said grates, means for feeding refuse to the rearmost grate, andmeans for removing sinter.

2. An incinerator according to claim 1 which further includes a seriesof air ports in each side wall of said chamber elevated above each ofsaid grates, each air port of each series being disposed at a differentvertical angle directed at a difierent zone of said grate so that thesum of the transverse areas of the grate toward which said air isdirected by each of said ports comprises the entire grate, and means forsupplying heated air to said ports.

3. An incinerator comprising a plurality of traveling grates, each gratefrom rear to front being at a lower elevation and arranged to receivethe discharge from the next upper grate, means for depositing refuse onthe uppermost grate, means for conveying away sinter from the lowermostgrate, walls forming a chamber about said grates, a roof for saidchamber, said roof being stepped correspondingly to said grates, therearmost part of the longitudinal stretch of each step of said roofbeing inclined downwardly and rearwardly at about a 45 angle to break upstratification of gases within said chamber and promote turbulencewithin said chamber, the lowermost portion of each step being elevated asubstantial distance above the underlying grate to permit turbulent flowof gases over the top of each grate from the bottom to the top of saidchamber.

4. An incinerator according to claim 3 which further includes airnozzles in said roof at certain of said downwardly inclined partscommunicating with the interior of said chamber and directed downwardlytoward said grates and means for supplying air to said nozzles.

5. An incinerator according to claim 3 which further includes a seriesof air ports in side walls of said chamber above the level of each ofsaid grates, each air port or" each series being disposed at a differentvertical angle directed at a different zone of said grate and means forsupplying air through each of said ports, said ports being directed todischarge air to sweep the entire area of the top stretch of each grate.

6. An incinerator according to claim 3 which further includes air portsin side walls of said chamber above the level of each said grates, meansfor supplying air through each of said ports to sweep the entire area ofthe top stretch of each grate, and air nozzles in said roof at certainof said downwardly inclined parts, said nozzles communicating with theinterior of said chamber and directed downwardly toward said grates, andmeans for supplying air to said nozzles.

7. In a refuse incinerator, means forming an elongated incineratorchamber, a stepped series of traveling grates in said chamber arrangedso that each grate discharges upon the next lower grate, a plurality oftransverse louvers below at least one of said grates arranged so that inclosed position said louvers form a continuous, air-tight floor beneathsaid grate closing the bottom of said grate against the entrance ofexcess air from the underside of said grate, means operable to tilt saidlouvers from closed position to permit discharge of fines through saidlouvers, a movable water-tight conveyor beneath said louvers positionedto receive the discharge of fines through said louvers, the upperlongitudinal run of said watertight conveyor being substantiallyimpervious to water passing downwardly thereon from above, said conveyorextending beneath the discharge end of the lowermost of said grates toreceive the sinter discharge theretrom, and a Water spray disposed abovesaid conveyor and directed toward said watcrtight conveyor to quenchmaterials thereon.

References Cited in the file of this patent UNITED STATES PATENTS105,317 Dee July 12, 1870 231,208 Bresnahan Aug. 17, 1880 344,631 CraneyJune 29, 1886 468,482 Loughran Feb. 9, 1892 676,930 Woes June 25, 1901837,887 Rock Dec. 4, 1906 839,754 Hall Dec. 25, 1906 1,240,737 LambSept. 18, 1917 1,376,843 Underwood May 3, 1921 1,388,714 Hofmann Aug.23, 1921 1,447,681 Michie Mar. 6, 1923 2,060,067 Greenwalt Nov. 10, 19362,389,077 Peterson .d Nov. 3, 1945 2,481,504 Ferro Sept. 13, 1949FOREIGN PATENTS 568,160 Great Britain Mar. 21, 1945

